Sample Preparation Using Oxygen Bomb Combustion

3 Sample Preparation Using Oxygen Bomb Combustion 

Method. Weigh accurately approximately 1.0 g of each cyanoacrylate adhesive into a cup attached to the lid of the oxygen bomb combustion vessel. To the vessel add 5.0 ml of water and fill with oxygen to 30 atm. The bomb is fired according to manufacturer s instructions. 

All samples prepared by each method are in aqueous solution and measured against an aqueous standard calibration curve prepared from a certified 1000 ppm stock standard to give 0.0, 0.5, 1.0, 2.5 and 5.0 ppm Nb in 0.5 M HNO3. 

Results of analysis of cyanoacrylate adhesives listed in column 1 of Table 6.1 using the three destructive methods are given in Table 6.4. 

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Sample Preparation of Anaerobic Adhesive Using Oxygen Bomb Combustion... 

The first step in analysing plastics for metals content in polymers by ICP-AES technique is that they must be prepared in solutions that are suitable for nebulization. There are four general methods applicable for sample preparation for metal analysis by ICP-AES and they are solvent dissolution of some plastics dry ashing using a muffle furnace acid digestion using a microwave oven and oxygen bomb combustion. 

Digestion of samples using high pressure oxygen bomb combustion is an excellent technique for sample preparation, particularly trace metal analysis. This technique can be applied to most plastics provided that small sample ( 0.25 g) of fine grain sizes of plastics are used. The solutions obtained are clean and easily analysed for metal content against standards prepared in the same solution added to bomb. 

Table 5.18 Results of comparative study of analysis of 250 ggkg-1 of spiked toxic metals after sample preparation using microwave acid digestion and oxygen bomb combustion. Results in brackets are percentage recovery...

The Parr oxygen combustion bombs were used for a rapid ash determination and for sample preparation for IC. About 0.5 g of shale or shale oil was mixed with 0.5 g of white oil in a stainless steel cup. Five mL of water was placed in the bottom of the bomb which was then assembled and pressurized to 30 atmospheres of oxygen. After combustion, the bomb was allowed to cool for ten minutes and then opened slowly. The inside walls of the bomb were washed with water, and all the washings were combined, filtered if necessary, and diluted to 50 mL. The residue in the cup was dried at 110°C for 15 minutes and reweighed for ash determination. 

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